Unicellular animals. Giants of the microbial world - the largest single-celled organisms

Despite the fact that most people eat the very obvious eggs of birds and fish almost every day, the words “single-celled organism” conjure up something that can only be seen with a microscope. Indeed, the vast majority of single-celled creatures do not exceed dimensions of hundredths of a millimeter, and this can be explained by a number of factors. It is more difficult for large living cells to maintain structural integrity, it is more difficult to transport food and waste within the body, in addition, impressive growth requires a fair amount of energy, which is evolutionarily disadvantageous.

But the world of microbes is rich in species, old and diverse, and therefore full of exceptions to the rules. And some organisms, to which the prefix “micro-” would be attached, despite the evolutionary benefit, do not achieve anything at all. Which, naturally, delights and fascinates.

Trumpeter ciliate

This freshwater creature resembles the trumpet of an ancient gramophone and grows up to 2 mm in length, so the trumpet ciliate can be studied without instruments. Protozoa of the genus Stentor are well known to microbial enthusiasts. Two millimeters does not seem super long, but many of nature's multicellular children take up much less space in their habitats and on glass slides.

What makes the trumpeter ciliate a colossus in the world of small fry is its anatomy. Unlike ordinary eukaryotes, Stentor contains not one, but several nuclei. This makes his daily work of maintaining his spirit easier. In the case of this ciliate, numerous small nuclei are responsible for reproduction, and a large nucleus - the macronucleus - manages everything else, playing the role of a kind of brain center.

The body of the trumpeter is covered with cilia of different lengths. Their friendly movements allow the ciliates to swim. These microcosm colossi feed on, for example, silt. The function of the mouth is performed by the narrow end of the “pipe”. At the same time, some bacteria, small protozoa, and even tiny unlucky multicellular organisms end up in the food.

Bahamas Thunder

One day, scientists from the University of Texas went to the bottom of the sea near Bahamas and discovered there, in the gloomy depths, dozens of unusual spherical objects the size of grapes. These objects seemed motionless, but clearly left traces in the sand up to half a meter long. At first, experts thought about some unknown mollusks or even strangely behaving poop. The truth was amazing, because the mysterious piles turned out to be spherical protozoa with a diameter of up to 3 centimeters. Which rolled along the bottom of the sea in almost zero temperature water.

The Bahama Gromya is an amoeba-like organism with a shell that is soft and porous. Pseudopodia are inserted into the holes in it, with the help of which the gromia moves along the bottom, feeding on organic matter caught along the way.

The discovery of this creature changed some views on the evolution of living beings, since it was previously believed that multicellular animals with bilateral symmetry were the first to learn to crawl back in Precambrian times. And the traces that gromia leaves are very similar to ancient fossilized prints that are almost 2 billion years old.

Unfortunately, little is known about these cytoplasmic balls because it is very difficult to get live Gromia specimens into the laboratory. Despite their shells, protozoa are very fragile and vulnerable. Scientists say that they are much softer than grapes, which these giant microbes are somewhat similar to.

Acetabularia

Known as the “mermaid glass,” Acetabularia is a unique genus of green algae similar in shape to cap mushrooms. These plants of shallow tropical seas are up to 10 cm in length and usually grow in groups, attaching their legs to bottom stones and showing off their light green caps.

Typically, large single-celled creatures have more than one nucleus, which is not the case with the amazing Acetabularia, which spends most of its life with just one giant DNA container located at the base of its “stalk.” Only at the hour of reproduction are additional nuclei formed, migrating to the top of the algae, where they turn into spore-like cysts, which, after wintering and complex transformation, become young acetabularia. Life cycle These colossal coenocytes are about three years old.

In experiments carried out with Nazi money in the 1930s and 40s by German scientist Joachim Hammerling, it was found that after one species of acetabularia is transplanted with the nucleus of another species of algae, the original plant begins to form a new cap, transforming into an unusual hybrid.

In addition, the “glass from which mermaids drink” perfectly regenerates when damaged, which is very reminiscent of some multicellular species of the world of flora and fauna.

Bellied Valonia

Some call this funny shallow-water creature “the eye of a sailor,” others simply call it “a bubble algae.” Wallonia potbellied easily grows up to 4 cm in diameter and even more, one organism is one living cell with many nuclei, most often territorially solitary and always similar to a polished greenish pebble. Sometimes small “multicellular organisms” also take root on the surface of this unicellular marine miracle.

Despite the biological strangeness and exotic appearance of the algae, the pot-bellied wallonia is not favored by the owners of large marine aquariums. If a plant accidentally invades, it will take over the entire bottom, making it terribly difficult to get rid of. Crushing or tearing this tenacious weed into pieces is not the case, because it is through cell division that the pot-bellied wallonia with its “collection” of nuclei reproduces.

Caulerpa thyssolifolia

You might think of it as if it were some kind of fern, but in essence this plant is much simpler. And much more decisive in growth. What appears to an inexperienced diver to be thickets of underwater flora will actually turn out to be one or just a few living cells, “masquerading” as complex multicellular bushes. These primitive creatures are called "caulerpa taxifolia", or simply caulerpa herringbone, an amazing creeping thyssolid stem. One cell of this green algae, with its countless DNA stores, can very quickly expand almost three meters in width, which regularly happens in the Mediterranean Sea, destroying the healthy ecology of the depths there. For this reason, the herringbone caulerpa is recognized as a particularly harmful weed. In California, this “giant microbe” is generally considered an illegal species.

The Mediterranean variety of thyssolist caulerpa, whose cells reach record sizes, owes its status as a pest to humans. Just half a century ago, this unusual algae did not live at all in the Mediterranean Sea. But in the 1970s, an aquarium in Germany ordered specimens of caulerpa from the tropics, but not just for beauty and easy care. Inquisitive Germans subjected the “Christmas tree” to technical abuse. The macrophyte was irradiated with ultraviolet light and treated with chemical mutagens. The result was a single-celled monster, growing very quickly and resistant to low temperatures. The cold-resistant and attractive-looking algae was released into the Mediterranean Sea in 1980 - some amateur aquarist from Monaco tried.

In four years, the inevitable happened. After escaping from the aquarium, the mutated caulerpa victoriously occupied the coastal waters of the Mediterranean. Unlike its natural counterpart, the mutant cell turned out to be not only aggressive, but also resistant to pollution. Moreover, it is capable of regenerating from a piece only a centimeter in size. And poisonous. Attempts to clear the resort's shallow waters of caulerpa thickets failed.

Therefore, at the end of the 20th century, the nickname “killer algae” was assigned to the single-celled organism “Caulerpa taxifolia”. The plant is included in the hundred most dangerous invasive species, stopping the spread of which is the sacred duty of every concerned earthling.

Amoeba Chaos

Imagine an amoeba from a school textbook. Increase it to the size of a sesame seed. You will get the creature Chaos carolinensis. Since such protozoa constantly change shape, the champions among chaos are able to stretch up to 5 mm in length. Such heavy single-celled organisms can be fatally wounded simply by covering them with a microscope slide.

Despite its impressive size, Chaos carolinensis behaves in the same way as its microscopic pseudopod-bearing relatives. With the help of pseudopodia, chaos move, and they also grab food. The food in the vacuoles is then digested alive, and the remaining waste is thrown out of the cell to the outside. The huge amoeba feeds on microbes of other species, as well as small animals such as cladocerans. Chaos will eat almost non-stop until it is ready to reproduce.

Like its neighbors on the list of giants of the microbial world, unicellular chaos has many control centers, simply because one nucleus is not able to control such a massive cell. Depending on size, Chaos carolinensis can have up to 1000 nuclei.

Spirostomum

The ciliate spirostomum can be found and seen in both fresh and salt waters. And mistaken for some little worm. The elongated body of the spirostomum reaches a length of 4 millimeters. Only when looking through the microscope eyepiece does it become clear that this mobile creature is one large and very long cell, covered with a dense forest of cilia.

Spirostomum is the champion of the microbial world in its ability to change body volume. When disturbed, a ciliate can shrink by 75% in less than 1/200 of a second - faster than any other living cell.

Unlike the voracious trumpet ciliates, Spirostomum does not eat multicellular creatures, but only gets by on bacteria. Giants reproduce by simple division and really don’t like it if there are heavy metals in the water, which makes these ciliates friends of ecologists.

Siringammina is the most fragile

Another useful candidate for the title of the largest single-celled creature on Earth is a fragile “monster” from the xenophyophore class. This class of “carrying other people’s bodies” organisms includes many inhabitants ocean floor, clots of cytoplasm that build for themselves in eternal night fragile wicker “houses” made from the remains of other creatures, for example, sponges or radiolarians. Xenophyophore cells make construction glue themselves, following commands coming chemically from numerous nuclei that float in massive clumps of cytoplasm. The largest of these clumps reaches 20 cm in size, is readily colonized by worms and bears the specific name Syringammina fragilissima.

Unfortunately, the life and biology of syringammina (“sand flute of Pan” in translation) is still little studied. Scientists suspect that this single-celled bacteria feeds, but no one has seen what the process itself looks like. There is an opinion that the fragile syringammina grows microbes for its diet within itself. The mechanism of reproduction of these rhizaria is also unclear.

The fragile deep-sea creatures were discovered in 1882 by the Scots, off their native North Sea shores. Subsequently, syringammin was found on the shelf of northern Africa.

Their name is legion...

Among the terrestrial unicellular giants special attention deserved, of course, meter-long slime molds, inhabitants of dead wood. Which at first and for a long time were mistaken for mushrooms.

However, slime molds (in particular, multi-headed Fusarium) turned out to be not only more primitive, but also in some ways much smarter than mushrooms. You can read about the interesting conclusions of Japanese scientists in this regard in the material.

The work provides Interesting Facts from the life of various groups of animals. I hope that using this information will make the lesson more interesting when studying the Zoology course. This information may interest students and become an incentive when studying biology: find interesting information about animals and provide them as creative work in the form of messages or presentations.

The selection of material is made on the basis of information from the Internet, as well as from popular science literature. 1. Teremov A., Rokhlov V. Entertaining zoology. AstPress, 2002. 2. Records of nature. comp. Makarova N.E. Minsk.Modern writer.2001

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MOST – THE MOST INTERESTING ANIMALS

PROTOZOA (SINGLE CELL)

The best of the best…

The biggest of the ever existing unicellular organisms - marine rhizomes of foraminifera. The calcareous shells of these protozoa, which lived more than 70 million years ago, reached a diameter of 22 cm.

The fastest Among the protozoa, the representative of the flagellates Monas stigmatica is considered. This single-celled organism can cover a distance 40 times the length of its body in 1 second (if a person moved at such a speed, then in a second he would cover an average of about 66 meters with a height of 165 cm).

This is interesting…

1. In one tablespoon sea ​​sand There are 100 - 200 thousand shells of dead marine unicellular rhizomes - foraminifera.
2. Empty shells of dead sea rhizomes, accumulating over millions of years, formed thick layers of calcareous (sedimentary) rocks. Common school chalk is an accumulation of small shells of marine unicellular animals.
3. One cubic centimeter of the contents of a cow’s stomach contains up to a million special single-celled ciliates that ensure the digestion of the hard cell membranes of plants. The total mass of ciliates inhabiting the stomach of one cow reaches 3 kg.
4. In a dormant state (cysts), the protozoa remain viable for more than 16 years.
5. The offspring of one ciliate - the slipper - could amount to 75 10 individuals in a year (provided that all descendants survive)! A hollow ball, touching one side of the Sun and the other of the Earth (the distance from the Sun to the Earth is 170 million km), could accommodate so many ciliates.
6. The digestive system of termite insects that feed on wood contains protozoa that help termites digest the hard shells of plant cells.

COELENTERATES

The best of the best…

The largest The coelenterate is an Arctic jellyfish, Cyanaea capillata, that lives in the northwestern Atlantic Ocean. One of the representatives of this species, washed ashore during a storm, had a bell diameter of 2.28 m, and its tentacles were 36.5 m long.

The most dangerous coralzoantaria Palythoa, the stinging cells contain polytoxin - the most potent poison of all those studied; 0.01 mg of this poison can kill an adult mouse.

Longest tentaclesin grooved anemone, with a diameter of 1.5 m.

The most poisonous jellyfishAustralian sea wasp and chiropsalmus jellyfish. The poison secreted by chiropsalmus acts almost instantly; If a person is not given medical assistance, death occurs within 5-8 minutes.

The most dangerous The coelenterate is an Australian box jellyfish sea wasp. It is considered the most poisonous animal in the world. Its poison paralyzes and stops the human heart within 1 to 3 minutes.

The largest coral reef(a colony of tiny coelenterates that form a protective calcareous skeleton around themselves) is the Great Barrier Reef on the northeast coast of Australia. Its length is 2027 km, its width is 72 km, and its total area is 207 square km.

This is interesting…

1. The venom of the physalia jellyfish is similar in its effect to the venom of a cobra.
2. From 1/200 of a damaged hydra, a new organism can be grown.
3. The maximum swimming speed of jellyfish is 55 km/h.
4. Many jellyfish have an exorbitant appetite. Thus, one Black Sea aurelia with a bell diameter of 50 cm absorbs about 10 fry per hour (1 fry in 6 minutes).
5. The body of most jellyfish is formed by a gelatinous mass (mesoglea), consisting of 98% water and a small amount of collagen protein, which in humans is part of the skin.
6. In ancient and medieval times, red coral mined in the Mediterranean Sea was valued much higher than such gems like emerald or ruby.

WORMS

The best of the best…

The longest Of all worms, the representative of marine polychaete worms is considered to be the nemertean, which lives in the seas of the North-West Atlantic. The worm, washed up in a storm in 1864 off the coast of Scotland, was about 55 meters long.with a diameter of only 1 cm.

The biggest a species among earthworms, or earthworms, is the Australian earthworm, reaching a length of almost 3 m with a diameter of 2.5 cm.

This is interesting…

SHELLFISH

The best of the best…

Most least commonmollusks are considered to be from the group of brachiopods, or armopods. Only 280 species are known to science and all of them are extremely rare.

The largest marine gastropoda whelk found off the coast of Australia in 1979 had a shell 77.2 cm long and a girth of 1.01 m. Its live weight reached almost 18 kg.

The most poisonous gastropodfrom the family of cones, cone-geographer. The mollusk's poison can kill a person.

The largest bivalve mollusktridactic. In 1956, a specimen measuring 1.15 m and weighing 333 kg was found off the coast of Japan. When alive, it probably weighed just over 340 kg.

Largest eyehas a giant Atlantic octopus. The record specimen was discovered off the coast of Canada in 1878. The diameter of his eye was 50 cm.

CRUSTACEANS

The best of the best…

The largest Among all crustaceans, the giant Japanese crab macrocheira, which is also called the crab on stilts, is considered. Adult representatives of this species have claws with a span of 3.5 m. Such specimens weigh about 18 kg.

Lowest pressurein lobster, which reaches 8 mmHg.

The largest crustaceantaka-ashi-gani, or giant spider crab, claw sizes reach up to 3.7 m and weight up to 19 kg.

The heaviest sea crustaceanA North American lobster weighing up to 20 kg and more than 1 m long was caught in 1977 off the coast of Canada.

The hardest The crustacean is the American, or North Atlantic, lobster. In 1977, a lobster weighing 20.15 kg and more than 1 m in length was caught in Canada.

The smallest crustacean - water flea. Its body length is less than 0.25 mm. Lives in water bodies of Great Britain.

The longest livingamong crustaceans are American lobsters; especially large specimens live up to 50 years.

This is interesting…

1. The blood (hemolymph) of crustaceans is in many cases colorless. But some, for example, decapod crayfish, which include crayfish, have blood of blue color. This is due to the presence of hemocyanin pigment containing copper. In other crustaceans, the blood, just like in humans and other mammals, is colored red by the pigment hemoglobin, which contains iron.
2. Male barnacle crustaceans have sperm up to 6 mm long. This exceeds the length of the animal itself by 10 times and is an absolute record in the animal world.
3. The chitinous shell of crustaceans is impregnated with calcium carbonate (lime). Such a rigid exoskeleton prevents the growth of the animal, so periodically the cancer sheds its old cover (molts). During molting, while the new chitinous cover has not yet hardened, the animal actively grows. A crayfish that has just molted usually eats the discarded old close cover in order to make up for the lack of lime and make the new cover more durable.

Arachnids

The best of the best…

The biggest A representative of arachnids is the tropical tarantula spider, which lives in the northeast of South America. A male of this species caught in 1965 had a limb span of 28 cm. A female caught in 1985 in Suriname weighed 122.2 g.

The fastest spiderslong-legged sun spiders that reach speeds of over 16 km/h.

The noisiest spiderThe European buzzing spider produces a buzzing sound audible to the human ear, and the purring spider produces sounds reminiscent of a cat's purr.

The largest among scorpionsconsidered to be the imperial scorpion, which lives in Equatorial Guinea. Adult specimens of this species, which are black in color, weigh up to 60 kg.

underground scorpionThe species Alacran tartarus was found in caves more than 800m deep.

The smallest representative of spidersis a spider native to Western Samoa. Its body size is only 0.43 mm, which corresponds to the size of a typographic point.

The fastest Among the arachnids there are long-legged salpugs that live in Africa. Some salpugs can reach speeds of up to 16 km/h over short distances.

The largest fishing netWeaver spiders build from webs: the circumference of their web is about 6 m.

The simplest webthe American spider has a bolas using a single thread

The strongest threadin Achaearenea tepidariorum, capable of catching a small mouse, which will hover above the ground.

The most poisonousBrazilian “stray” spiders are considered; they secrete poison with a strong nerve-paralytic effect. These large, aggressive spiders often enter homes and hide in clothing and shoes. When disturbed, they bite several times in a row. The Central Asian karakurt spider, called the black death, has also gained a very bad reputation; it is also very poisonous.

This is interesting…

1. The arachnoid glands of spiders open on the abdomen with arachnoid warts and secrete several types of web - dry, wet, sticky, corrugated, etc. Different varieties of web serve different purposes - making a hunting net, a living house, an egg cocoon.
2. The thread produced by spiders is very strong: the breaking load for a web ranges from 40 to 261 kg per 1 square millimeter of cross-section. Steel wire of the same diameter is less strong than spider web.
3. Accurate studies of American scorpion venom have shown that 0.0003 mg of this poison per 1 g of mouse weight is a lethal dose. When stinging, a scorpion injects significantly more venom into the victim - more than 3 mg. This amount of poison can kill mice weighing a total of 10 kg.
4. A dog tick that has sucked blood weighs 223 times more than a hungry tick. During the 3 weeks it takes a bull tick to develop from a larva into an adult arachnid, it sucks so much blood that it increases its weight by 10,000 times.
5. One scientist, observing the activity of a weaver spider, recorded the speed of web thread production - 180 cm per minute - and extracted about 140 m of web.
6. The proboscis of blood-sucking ticks has a special apparatus of hooks directed backwards. These hooks act as a holding anchor device, allowing the tick to firmly attach to the host's skin. Simultaneously with the introduction of the proboscis into the skin, the tick injects saliva into the wound containing ixodine, a substance that prevents blood clotting. In the same way, various infections are transmitted into the circulatory system of the host body.
7. Scientists have found that the web thread released by spiders carries a small negative electrical discharge. Spiders need webs not only for hunting. Thus, young spiders disperse in nature, gliding on spider threads and flying vast distances. At the same time, air travelers never collide with each other in flight, and their webs do not touch upon landing. This occurs due to the electrostatic repulsive forces of like (negatively) charged webs.

INSECTS

The best of the best…

The most prolificOf the multicellular animals on the planet, insects are considered. Thus, it is estimated that under favorable conditions, the mass of the offspring of just one female cabbage white butterfly per year can be 822 million tons, which is 3 times the weight of the entire population of our planet.

The largest termitesMacrotermes goliaph reaches a length of 2.2 cm with a wingspan of 8.8 cm.

The largest grasshopper in the CIS countriessteppe rack 7.5 cm long.

The most gluttonousOn the planet, insects are also considered animals. So the caterpillar of one of the butterflies North America in the first 48 hours of life, it absorbs an amount of food that is 86 thousand times its own weight.

The most greedy insectIn the first 56 days of life, the caterpillar of the polyphemus butterfly absorbs food, the volume of which exceeds the weight of the caterpillar by 86 thousand times.

The strongest Among the animals are insects: tests have shown that the rhinoceros beetle can support 850 times its own weight on its back. The forest dung beetle is capable of moving a load 400 times its own weight.

The largest clustersinsects form in one place. According to the calculations of one American scientist who observed a swarm of locusts, the area occupied by it was 514,374 square kilometers. Presumably there were up to 12.5 trillion locusts in it, and its total weight was at least 25 million tons.

The most dangerous The animals on our planet are considered to be malarial mosquitoes that carry the causative agents of malaria - the single-celled protozoan malarial plasmodia. Over the entire history of mankind since the Stone Age, malaria has killed half of the entire population of the Earth. Even today, malaria affects more than 200 million people a year.

The largest and heaviestAmong the insects, goliath beetles are considered, living in Equatorial Africa. The weight of adult males of the royal goliath reaches 100 g, and the length is 11 cm.

The longest The world's largest insects are giant stick insects from Indonesia. Females of this species reach a length of 33 cm. The longest beetle (excluding the length of the antennae) is considered to be the Hercules beetle, which lives in the Central and South Africa. Its body length is 19 cm.

The biggest In the world, the diurnal butterfly is the Alexander birdwing, found in New Guinea. Females of this species have a wingspan of more than 28 cm. The largest nocturnal butterfly is considered to be the rare Agrippina moth from Brazil, whose wingspan reaches more than 30 cm.

The smallest The moth that lives in the Canary Islands is considered the world's butterfly: its wingspan is about 2 mm.

Most higher speed flight among insects is developed by dragonflies. So, the Australian dragonfly can a short time reach a speed of up to 60 km/h. Tropical cockroaches run faster than all other insects. A cockroach about 3 cm long moves at a speed of 120-130 cm/s (that is, in a second it covers a distance more than 40 times the length of its body).

The most acute sense of smellThe male emperor moth has the ability to smell a female 11 km upwind. It was found that the smell comes from a special substance secreted by the female in a negligible amount - 0.0001 mg.

This is interesting…

1. Dragonfly wings have special thickenings at the ends. These thickenings eliminate the harmful vibration of the wings that occurs during flight - flutter. The elimination of flutter in modern high-speed aircraft was achieved in a similar way - by thickening the leading edge of the wing.
2. Extinct ancient dragonflies that lived more than 200 million years ago were enormous in size: their wingspan reached 90 cm.
3. The songs of crickets, locusts and grasshoppers are chirping sounds produced by the friction of one part of the body against another. Some species of these insects have a series of tubercles on the inside of the thighs of the hind legs. The sound occurs when the raised leg rubs the tubercles against the forewings.
4. The compound eyes of insects consist of many individual simple eyes called ommatidia, or facets. The number of simple eyes depends on the activity of the insect and its lifestyle: for example, in a dragonfly, which is a predator, each eye contains 20-30 thousand facets, in a fly - 4000, in a butterfly - 1700, in an ant - 1200. Any moving object consistently falls into the field vision of each simple eye, so the insect can accurately determine the speed of a moving object. Based on these features of ommatidia, a device was designed that could instantly measure the speed of aircraft. Traffic police officers have the same devices - radars that measure the speed of a car.
5. These blood-sucking flies appear only with the onset of autumn. They bite painfully. Some believe that these are ordinary house flies that become so angry in the fall. In fact, these are completely different flies and they are called zhigalki.
6. At the slightest danger, the bombardier beetle releases a caustic hot substance, the temperature of which reaches + 100 degrees, from the holes located on its abdomen. At the same time, a loud bang is heard. The beetle's abdomen is very mobile and it can “shoot in bursts.”

FISH

The best of the best…

The largest sea ​​fish is considered a plankton-eating whale shark that lives in the warm waters of the Atlantic, Pacific and Indian oceans. The exact dimensions of one of the captured whale sharks were: 12.65 m in length and 7 m in girth at the thickest part of the body. The weight of this fish reached 15 tons.

The thickest skinCalifornian and Mediterranean moray eels possess, which cannot be cut with a knife or pierced with a hammer, and cannot be penetrated by a bullet.

The largest marine predatory fishis the white shark Carcharadon, often called the man-eater shark or the white death. Adult fish of this species reach an average length of 4.5 m and weigh 520–770 kg. However, there were cases when larger specimens were encountered. Thus, a female white shark measuring almost 6.5 m long and weighing 3310 kg was caught off the coast of Cuba. This shark's liver alone weighed 456 kg.

The largest bony fishconsidered to be an ordinary herring king, distributed in almost all seas and oceans. In 1963, American scientists from the Sandy Hook Marine Laboratory saw a fish whose length was more than 15 m. Presumably, it could weigh about 500 kg.

The most cruel fishsharp-toothed piranhas that attack any creature that is wounded or struggling in the water.

The most powerful bitebelongs to a dark shark that developed a force of 60 kg, which is equivalent to a pressure at the tips of the teeth of 3 t/cm2.

The heaviest among bony fishis a moon fish widespread in all oceans, often swimming on its side. A fish measuring 4.3 m long and weighing 2235 kg was caught off the coast of Australia.

The most prolificAmong fish, the moon is also considered a fish. During one spawning, females spawn up to 300 million eggs. However, over the next year, less than 1% of the juveniles survive from this number of eggs. The rest die, eaten by a variety of aquatic predators.

The most acute sense of smellin sharks, capable of detecting the presence of one part of mammalian blood in 100 million parts of water.

The largest freshwaterThe fish is considered to be the European catfish. So, in the 19th century, catfish were caught in Russian rivers; their length was 4.6 m and their weight reached 340 kg.

The fastest Among the fish, the Pacific sailfish is considered. At short distances, this fish with a sword-shaped outgrowth on its head and a high dorsal fin can reach speeds of up to 109 km/h. Bluefin tuna is slightly inferior to the sailfish, capable of reaching speeds of up to 104 km/h.

The longest livingThe fish is the Japanese koi fish, a type of mirror carp. It is known that the age of a fish can be determined by the number of age rings on its scales (just like the age of a tree - by the number of growth rings). Thus, a koi that lived in one of the ponds in Japan had the number of age rings on its scales corresponding to 228 years.

The most poisonous fish in the worldis considered a wart that lives in the tropical waters of the Indian and Pacific oceans. It has the largest venom glands among fish, opening into ducts on the needles of its fins. The poison contains a substance called tetrodotoxin, which has a neuroparalytic effect. Touching the fins of this fish is fatal to humans. Death occurs within a few minutes from cessation of breathing and cardiac activity. Interestingly, a fish closely related to the warty fish, fugu, is eaten in Japan. True, every cook who wants to prepare dishes from this fish is required to obtain a diploma from a special school and pass an exam in which he himself must eat the fish he has prepared.

This is interesting…

1. It is known that buoyancy, that is, the ability to effortlessly stay in the water column, is the most important feature of most fish. But it is achieved in different ways: bony fish have a swim bladder, cartilaginous fish (sharks and rays) accumulate fat reserves in the liver and other organs and tissues of the body, which reduces the density of the fish’s body in relation to the density of water.
2. The Nile pike is capable of creating electrical discharges with a frequency of up to 300 pulses/s.
3. There are more than 40 species of flying fish. Among them, the most common are longfins and bats - small fish with a body length from 20 to 50 cm.
4. The muscular system of electric fish - torpedo rays, electric eels, Nile pike, etc. - produces biological electricity. Each such “electric battery” consists of 400,000 – 1,000,000 “elements”. Fish have an electrical charge of fairly high power and strength. Thus, the average representative of the electric eel can produce an electrical charge of 400 volt-amperes. There have been cases when particularly large specimens of eels produced a current of 650 volt-amperes.
5. In 1961, the English ship Leopold was rammed by a swordfish. The ship's steel plating was punctured and leaked heavily. The sailors had to call a rescue plane with an emergency crew. In the past, in England they even insured ships against attacks by living swords.
6. The expression “dumb as a fish” is far from the truth. Fish squeak, wheeze, click, squeal – a whole cacophony of sounds can be heard using special devices. The most chatty fish is the trigla, or gurnard. With the help of her swim bladder, she makes sharp sounds similar to grunting or snoring.
7. The extinct ancestors of the white shark, or man-eating shark, which lived in the ancient seas more than 70 million years ago, reached a length of 30 m. The teeth of these fossil sharks were up to 13 cm long, and a passenger car could easily fit in their open jaws.
8. It is estimated that one tiger shark can grow, use and shed up to 24 thousand teeth in 10 years.
9. A shark smells blood, even if 1 g of blood is dissolved in 1000 liters of water.

Amphibians, or AMPHIBIANS

The best of the best…

The largest amphibian- gigantic salamander. This is a very rare animal that lives in the mountain rivers and streams of Southern China. It reaches a length of 1.6 m and can weigh over 30 kg. For example, a salamander caught in Huan Province was 1.8 m long and weighed 65 kg.

Longest frog jumpbelongs to the African sharp-faced frog. In the frog competition in 1977, she made a jump of 10.3 m.

The largest toad- yeah, living in Central and South America. It reaches a length of 25 cm and a width of 12 cm and can weigh more than 1 kg.

The smallest toadOn Earth, the Brazilian two-toed toad is considered - its length is only 1 cm.

The largest of the green frogslake frog, reaching more than 15 cm, living in Germany and France. This is the same frog that the French eat.

The largest of all frog species- African goliath, which can be up to 40 cm long and can weigh up to 3 kg.

The smallest frog in the world- a dwarf frog that lives in Cuba; it barely reaches 12 mm in length.

The most powerful poisonsecreted by the skin glands - batrachotoxin - is possessed by the terrible leaf-climbing frog (cocoi), its length is only 2-3 cm, and it weighs no more than 1 g. It lives in the western part of Colombia. Local Indians smear arrowheads with the poison of this frog. An animal wounded by such an arrow becomes paralyzed and dies. The secretions of the skin glands of the cocoa frog are 20 times stronger than the poison of other poisonous frogs and can freely penetrate the pores of human skin. This is the most powerful non-protein poison known today. On average, one frog contains enough poison to kill 1,500 people, and 30 mg of poison from this frog is enough to kill 30,000 mice. The dried poison remainsdeadly for 15 years, it is 10 times stronger than the poison of puffer fish.

The most poisonous amphibians in our countryare considered different kinds toads: gray, green, reed. The skin of toads contains many poisonous glands, among which two large parotid glands stand out. When squeezed, the poison of these glands can be thrown out at a distance of up to 1 m. When it comes into contact with human skin, it causes burning and redness of the skin, but not the appearance of warts.

REPTILES, or REPTILES

The best of the best…

The largest reptileconsidered to be a saltwater crocodile that lives in Indonesia and Australia. Adult crocodiles of this species have an average length of 4.5 m and weigh about 500 kg. Once, a crocodile 8.6 m long and weighing more than 1 ton was killed.

The most ferocious dinosaurVelociraptor, sharp teeth and claws easily tore apart any prey.

The largest flying dinosaurswere Quetzalcoatlia, the wingspan was 12 m.

The dumbest dinosaurstegosaurus, the brain was the size of a walnut and weighed 70 g, with a length of 9 m.

The largest dinosaur clawswere found in therizinosaurus; the length of the outer curve of the therizinosaur's claw reached 91 cm.

The largest lizardis the Kabaragoya monitor lizard living in New Guinea: its length is 4.8 m including the tail. It is rivaled by the Komodo dragon from the Indonesian Komoda Islands. The largest specimen of this monitor lizard reached a length of 3 m and weighed 166 kg.

Longest lizardSalvadoran or Papuan monitor lizard, reaching a length of 4.75, the length of the tail is 70% of its total length.

The most dangerous lizardsgila monster and escorpion found in Mexico.

The largest sea turtleconsidered to be a leatherback turtle that lives in the waters of the Pacific Ocean. The length of adult turtles from head to tip of tail is about 2 m, weight reaches more than 450 kg. Record weight – 865 kg, length – 2.5 m.

The largest land turtleis a gigantic, or elephant, turtle with Seychelles– its weight reaches 300 kg.

The smallest turtleThe motley land turtle has a shell only 6-9 cm long, and the sea turtle is the Atlantic ridley, 50-70 cm long.

Deepest turtle divemade in 1987 by a leatherback turtle equipped with sensors, diving to a depth of 1,200 m in the waters off the Virgin Islands.

The largest of all snake species– anaconda, or water boa: the average length of an adult anaconda is 5.5-6 m. The record is length 8.5 m, weight – 230 kg, the girth of this snake’s body was 110 cm.

The largest poisonous snake- a king cobra, reaching a length of 5-6 m. Its poison can kill an elephant. Baby cobras can kill as soon as they hatch from the egg.

Fastest snakemamba. Its speed reaches more than 11 km/h

The longest snake fangshas a poisonous Gaboon viper from tropical Africa, reaches a length of 5 cm.

The most poisonous land snakeis a smooth-headed snake native to Australia. 110 mg of this snake's venom is enough to kill 125,000 mice.

The most dangerous species of crocodiles for humans- a large Indo-Pacific, or saltwater crocodile. Every year, crocodiles of this species kill up to a thousand people.

Longest living reptile, apparently, is a land-dwelling Seychelles giant tortoise. There are cases where turtles of this species lived in captivity for more than 150 years.

This is interesting…

1. A small amount of cobra venom has an analgesic effect and can be used as a morphine substitute for people suffering from cancer. Moreover, unlike morphine, snake venom acts longer and does not cause side effects or addiction to the body. Viper venom is successfully used as a hemostatic agent and is used in the treatment of hemophilia (hereditary incoagulability).
2. Gecko lizards can walk freely on almost vertical walls and ceilings, which is why they are sometimes called anti-gravity lizards. It turns out that on the soles of geckos' feet there are 18-25 rows of tiny sucker sticks. When the lizard places its foot on a support, air is squeezed out of the suction cups under the weight of the animal and a vacuum is formed. There are more than 1,000 of these sticks on each gecko leg.
3. There is an interesting pattern: the hungrier a poisonous snake is, the faster its victim dies when bitten, since a hungry snake releases more poison. After all, poison is altered saliva, and the poisonous glands are nothing more than the parotid salivary glands.
4. Recently, scientists have found out the reason for the famous “crocodile tears”, which serve to remove excess salts that enter the body along with food and water.
5. Animals have different sensitivities to snake venom. The least susceptible to it is the hedgehog - it can withstand a dose of poison 40 times greater than a guinea pig. The same dose of rattlesnake venom can kill 10 snakes, 24 dogs, 25 oxen, 60 horses, 6,000 rabbits, 8,000 rats, 20,000 mice, and 300,000 pigeons.
6. The collared cobra, sometimes called the spitting cobra, has a venom so strong that if it gets into the eyes of mammals and humans, it causes blindness for several days.
7. Snake venom is a truly strong cocktail of various proteins and enzymes. It has a destructive effect on living tissue, but does not play any role in digestion. The venom formula varies from snake to snake, but the most common venoms typically contain: a paralyzing agent nervous system, a component for stopping the heart, disrupting the movement of blood, as well as other components, some of which destroy the proteins of the victim’s tissues, others cause the formation of blood clots (blood clots), clogging blood vessels and stopping the movement of blood, and others cause extensive internal hemorrhages.
8. Since snakes cannot bite off pieces and chew their food, they swallow it whole. In snakes, the jaws are connected by movable elastic ligaments; thanks to this movable connection, the snake can move its jaws and open its mouth so wide that it swallows prey several times its size. The teeth of snakes are directed inward and this ensures that the prey slides in the right direction. In addition, snakes form great amount saliva to wet the prey and facilitate its sliding down the esophagus.
9. When studying the development of alligators, scientists found that at a temperature of +32 degrees, mainly females hatched from eggs, and at temperatures above +33.5 degrees, more males appeared. The same pattern is observed in the development of some turtles.
10. Some species of snakes, including rattlesnakes and pit vipers, detect prey by infrared radiation from its body. Under their eyes they have sensitive cells that detect the slightest changes in temperature, down to fractions of a degree, and thus orient the snakes to the location of the prey. This highly sensitive device allows the snake to find prey in complete darkness.
11. The senses of taste and smell are very important for snakes. The quivering forked tongue, which some people consider a “snake sting,” actually collects traces of various substances that quickly disappear in the air and carries them to sensitive depressions on the inner surface of the mouth, where a special device connected to the olfactory nerves is located.

BIRDS

The best of the best…

The largest flightless bird– the common ostrich, which is found in Central Ethiopia and Niger. Some males of this species reach 2.74 cm in height and weigh 156.5 kg.

The largest flying bird- African Bustard. Hunters shot birds that weighed about 20 kg. The mute swan can also reach a significant weight - up to 22.5 kg.

Largest wingspanhas the wandering albatross, found in the Southern Hemisphere. The wingspan of these birds reaches 3.6 m. Another bird with an average wingspan of 3.3 m is the African marabou. Thus, in Central Africa, a male of this species with a wingspan of 4 m was shot.

The smallest bird in the worldis a bee hummingbird that lives in Cuba: adult males reach a length of 5.7 cm, with half of this length accounting for the beak and tail. These little ones weigh about 1.5 g.

Highest flight speeddevelops the peregrine falcon: its speed in a dive towards prey can be 350 km/h. In horizontal flight, ducks and geese have the highest speed: it approaches 100 km/h.

Longest and deepest dive everEmperor penguins demonstrate. According to scientists, they can dive to a depth of 265 m and stay under water for about 20 minutes.

The sharpest visionin birds of prey. A golden eagle sees a hare in good light at a distance of 4.2 km. A peregrine falcon spots a pigeon 8 km away. However, the vision of birds of prey is black and white; they do not perceive color.

The largest nestsbuilt by bald eagles that live in the United States. Once a nest was discovered almost 3 m wide and 6 m high. The weight of the nest apparently exceeded 2 tons. It is possible that several generations of birds took part in the construction of such a nest over several years. Hatchery mounds built by egg-laying weed chickens in Australia reach 4.6m high and 10.5m wide. The weight of such a nest is more than 300 tons.

This is interesting…

1. Weed chickens living in Australia, unlike other birds, do not warm their eggs with the heat of their bodies, but hatch their chicks in “incubators” - they bury their eggs in mounds of sun-heated soil and rotting plants. These mounds, and sometimes they can reach quite impressive sizes, are raked by chickens with their paws. Birds manage to maintain a temperature of +33 degrees inside such structures, despite the vagaries of the weather. The hatched chicks dig their own way to the surface.
2. Egg white albumin is used for poisoning with salts of heavy metals, especially mercury and copper. It forms insoluble compounds with these metals, which delays their absorption into the body and, in combination with emetics, allows the body to quickly rid the body of poison.
3. The flight of birds, in comparison with other methods of animal movement, turns out to be more economical than walking or running. Large birds expend even less energy for the same flight distance than a jet airliner.

MAMMALS, or BEASTS

The best of the best…

The largest and heaviest mammal in the worldis a blue whale, the recorded length of the largest blue whale is 33.6 m. Another whale caught in Antarctica was 27.6 m long and weighed 190 tons. The weight of the animal’s tongue was 4.3 tons, and the heart was about 700 kg .

Fastest sea mammal– killer whale, capable of reaching speeds of up to 55 km/h.

The slowest of mammalsis a three-toed sloth native to South America. On the ground it moves at a speed of 1.5 - 2.5 m/min. In the trees it is somewhat faster - in a minute it covers a distance of about 5 m.

Deepest divehas been recorded in the sperm whale. The depth to which this type of whale can dive is over 2500 m. Once off the coast of Australia, a sperm whale was killed, which surfaced after a dive that lasted about two hours. Two small bottom-dwelling sharks were found in his stomach. And the depth of the ocean in this place reached 3200 m.

Longest sleepnoted in a ground squirrel living in Alaska. She sleeps 9 months of the year. For the remaining 3 months, this rodent eats, bears offspring and stores food in its hollow.

Longest gestation periodfor the Asian elephant - from 610 to 760 days (more than 2 years).

The fattest milkAmong mammals, female sperm whales have: it contains up to 54% fat. For one feeding, the baby whale receives 15-20 buckets of milk, thick as sour cream. Breastfeeding lasts 13 months from the moment of birth.

The most major representative carnivorous ordercounts polar bear. The average weight of males of this species is 380-410 kg with a body length of 2.5 m. Once in Alaska, a bear was killed that weighed more than a ton (1000 kg), its length from the tip of the fashion to the tail was 3.4 m.

The smallest representative of the order of carnivores- weasel. With a body length of 13-25 cm, this animal weighs 40-70 g.

The largest representative of the rodent orderis considered to be a capybara, or capybara, that lives in the swampy forests of South America. Animals reach a length of 1.4 m and weigh up to 110 kg. The largest rodent of our fauna, the beaver, reaches a length of 1 m and weighs over 30 kg.

The biggest hornsOf the currently existing animals, the Asiatic buffalo, which lives in India, has. The length of the horns, measured from the tip of one horn across the forehead to the tip of the other, was 4.3 m in one of the male buffaloes.

This is interesting…

1. The shape of the pupil in animals can be different. So, a goat has a square pupil, some antelopes have a stylized image of a heart, and domestic cats have a slit-shaped or fusiform pupil.
2. The mystery of how animals' eyes glow in the dark is not that complicated. The fact is that inner surface The eyes of cats, dogs and wolves have a reflective mirror layer - tapetum. It is not solid, but consists of small silvery crystals that collect weak rays from stars, the moon and other distant light sources. The reflected light varies in strength and color. It all depends on the shape, size and angle of rotation of the crystals.
3. Rodents' teeth are amazingly strong. Rats and mice chew through lead insulation and concrete, and one porcupine chewed a hole in a glass bottle.
4. The strong-skeletal shrew lives in Africa. The axial part of her skeleton is an interweaving of bone “reinforcement”, reminiscent of openwork metal structures. These animals are not in danger of being crushed, even if an elephant steps on their hole. The shrew itself, measuring no more than 10-12 cm, can withstand a load equal to the average weight of an adult.
5. Common vampire bats, or desmodes, found in South America, feed on the blood of warm-blooded animals. The vampire sits on a sleeping cow, horse or person so that the victim does not even feel it. With razor-sharp teeth, the vampire cuts off small pieces of skin until blood flows (a substance contained in the vampire's saliva prevents blood from clotting), folds his tongue into a groove and laps it up at high speed. In a year, one desmodus can drink up to 12 liters of blood.

In what ways did people make fire before the advent of matches? They rubbed wooden surfaces against each other, knocked out a spark with silicon, tried to catch a ray of sunlight through a piece of glass. And when they managed to do this, they carefully maintained the burning coals in clay pots.

Zimbabwe experienced the first positive effect of global warming. Previously, this process was associated for Africa only with increasing water shortages and rising sea levels. The deadly tsetse flies are almost gone from Zimbabwe due to warming. Over the past 10 years, those involved...

In the UK, seahorses are becoming extinct due to boats.

In popular tourist seaside destinations in the UK, pleasure boats are causing irreparable damage to the seahorse population, reports the Daily Mail. The bay in Dorset is the only place where both species of sea creatures have been seen, which are found...

Bacteria also die out, and do so quite often.

Bacteria are dying out at a significant rate. Although, apparently, they managed to avoid the mass extinctions that affected larger life forms on Earth. This was stated by scientists from the University of British Columbia, the California Institute of Technology and the National Laboratory...

Interesting facts about biology will be interesting not only for schoolchildren. Many adults are not even aware of many facts. They don't talk about this in class. All important facts in biology are classified and not everyone knows about them.

1.The length of the stalk of acetabularia algae can reach...

Black Sea: flora and fauna. Today, the fauna of the sea includes 270 species of algae: green, brown, red bottom (cystoseira, phyllophora, zoster, cladophora, ulva, etc.). Phytoplankton is very diverse - about 600 species. Among them are dinoflagellates, diatoms and others. Animal world

If...

Swifts, swallows.

Who among us has not looked at small, fast birds with forked tails flying rapidly in the pre-sunset sky, literally performing aerobatics, filling the air with piercing screams? It could be a swallow or a swift. The similarities and differences between these birds are usually...

Order Chiroptera: the whole truth.

Chiropterans are small animals, weighing from 2g (butterfly bats) to 1.5kg (flying dog). The distribution of representatives of the order Chiroptera is associated with climate conditions, they inhabit almost all corners of the earth, are not found in the tundra and Antarctica, and the most common habitat of chiropterans is...

The most dangerous snakes in Russia.

There are not too many species of snakes in Russia, but there is a danger associated with poisonous representatives of these reptiles. It is necessary to consider the most poisonous varieties of these creatures in order to be prepared for a possible meeting with them, and this article - the top 5 will help you deal with...
amoeba wikipedia, amoeba photo

Amoeba Ehrenberg, 1930 Amoeba

• (Latin Amoeba, from Greek αμοιβή - “change”) is a genus of microscopic unicellular organisms from the family Amoebidae. Amoebas have an irregular, constantly changing shape. It moves with the help of pseudopods (pseudopodia), which constantly appear and disappear.
• 1 Description
• 2 History of the study
• 3 Interesting facts

4 Notes

They are found in ponds, in moist soil, and in the entrails of animals. They reproduce by binary fission. The amoeba cell has a thin membrane, a large nucleus, nutrient and contractile vacuoles and fat globules. The secretions pass through the contractile vacuole. Length up to 0.5 mm. The most famous species is the amoeba proteus.

History of the study

The amoeba was first discovered in 1757 by August Johann Rösel von Rosengoff. Early naturalists called the amoeba Proteus after greek god Proteus, who could change his shape. The name "amoeba" was given to these microorganisms by J. B. Borys de Saint-Vincent, from the Greek word change (Greek αμοιβή).

In 1918, Dientamoeba fragilis was first described and shown to be harmful to humans.

• Amoeba is distinguished by its large genome length. Thus, the genome of the amoeba Amoeba dubia consists of 690 billion nucleotide pairs (for comparison, the human genome consists of 2.9 billion pairs).
• Many other single-celled organisms also have an amoeba-like form, including the killer amoeba Naegleria fowleri, which is dangerous to people because it eats their brains. This is a completely different organism - it belongs to a different class. This amoeba is found in warm waters, attached to algae. It enters the body through the nasal canals and feeds on the olfactory cells of the brain, causing primary amoebic meningoencephalitis, a fatal disease (mortality rate - 97%). Between 1995 and 2004, 23 cases of infection with the killer amoeba Naegleria fowleri were recorded. Infection with amoebas is possible through airborne droplets in hospitals and laboratories. Infection of the vaccination material is also possible. This infection is especially dangerous for infants and preschool children.

Notes

1. Amoeboid movement // encyclopedic Dictionary Brockhaus and Efron: 86 volumes (82 volumes and 4 additional). - St. Petersburg, 1890-1907.
2. "System of Nature"
3. Leidy, Joseph (1878). Amoeba proteus. The American Naturalist 12 (4): 235–238. DOI:10.1086/272082.
4. Audouin Jean-Victor. Dictionnaire classique d "histoire naturelle. - Rey et Gravier, 1826. - P. 5.
5. McGrath Kimberley. Gale Encyclopedia of Science Vol. 1: Aardvark-Catalyst (2nd ed.). - Gale Group, 2001. - ISBN 0-7876-4370-X.
6. Eugene H. Johnson, Jeffrey J. Windsor, and C. Graham Clark Emerging from Obscurity: Biological, Clinical, and Diagnostic Aspects of Dientamoeba fragilis.
7. Sizing up genomes: Amoeba is king
8. Killer amoeba eats human brain
9. Brain-eating amoebas linked to vaccinations

amoeba Wikipedia, amoeba pictures, common amoeba, amoeba structure, amoeba photo, amoeba is

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